• 한국작물학회지
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• 제47권6호
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• pp.448-452
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• 2002

벼 자동화 육묘시설에서 파종기별 적정 파종량을 선정하기 위하여 실험한 결과를 요약하면 다음과 같다. 1. 파종기에 따른 묘특성은 상자당 파종량이 증가할수록 초장은 커지는 경향을 보였으나, 묘충실도는 감소하였다. 2. 이앙기별 파종량에 따른 본답 생육 특성은 파종기에 관계없이 파종량이 증가할수록 이앙 초기에는 초장은 커지고 분얼수는 증가하였으나 이앙 40-50일 이후부터는 파종량간에 큰 차이를 나타내지 않았다. 3. 파종량에 따른 수량성은 5월 25일 이앙구에서는 파종량 간에 유의성이 없이 200g 파종구에서 수량이 가장 높았으며, 2모작인 6월 20일 이앙의 경우는 200-250g 파종까지는 유의성이 없었으나, 200-250g 파종구와 300g 파종구에서는 유의성 있는 차이를 보였다.

• 한국작물학회지
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• 제30권4호
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• pp.419-426
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• 1985

동부의 파종적기와 한계기를 구명함과 동시에 Growing Degree Days(GDD)의 이용 가능성을 검토하였던 바 시험결과를 요약하면 다음과 같다. 1. 파종기 지연에 따라 파종후 개화 및 성숙시까지의 일수가 단축되었으며 8월 14일 이후 파종은 개화하지 못했다. 2. 파종이 늦어질 수록 생육초기의 생장속도가 빨라졌고, 중원재래가 그 경향이 뚜렷하였다. 3. 5월 1일부터 7월 15일까지의 파종에서는 주경장, 주경절수, 분지수 및 경직경의 차가 없었으나 7월 30일 이후 파종부터는 파종지연 정도에 따라 급격히 감소했다. 4. 주경화경수, 분지화경수, 화경당착협수, 개체당착협수 및 100입중과 수량간에는 고도의 정의 상관관계가 있었다. 5. VITA#5는 중원재래에 비해 화경수, 개체당착협수가 않고, 100입중도 무거워 다수성이며, 두품종 공히 조파할 수록 증수의 경향이었고, 파종 한계기는 VITA#5가 6월 30일, 중원재래가 6월 15일 이었다. 6. 개화·착협 당시의 생육조건이 불량하면 협당입수가 감소된다. 7. GDD에 의한 개화까지의 표시방법은 일반 날자로 표시하는 것보다 변이계수가 작아 동부에도 이용가능성을 보였다.

• Transactions on Electrical and Electronic Materials
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• 제12권5호
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• pp.193-196
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• 2011

Lead zirconate titanate (PZT)/ bismuth ferrite (BFO) multilayer thin films have been fabricated by the spin-coating method on Pt(200 nm)/Ti(10 nm)/$SiO_2$(100 nm)/p-Si(100) substrates using $BiFeO_3$ and $Pb(Zr_{0.52}Ti_{0.48})O_3$ metal alkoxide solutions. The PZT/BFO multilayer thin films show a uniform and void-free grain structure, and the grain size is smaller than that of PZT single films. The reason for this is assumed to be that the lower BFO layers play an important role as a nucleation site or seed layer for the formation of homogeneous and uniform upper PZT layers. The dielectric constant and dielectric losses decreased with increasing number of coatings, and the six-layer PZT/BFO thin film has good properties of 162 (dielectric constant) and 0.017 (dielectric losses) at 1 kHz. The remnant polarization and coercive field of three-layer PZT/BFO thin films were 13.86 ${\mu}C/cm^2$ and 37 kV/cm respectively.

• 식물분류학회지
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• 제41권3호
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• pp.202-208
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• 2011

The present study was focused on the careful investigation of Glechoma longituba flowers collected from four populations in Korea to clarify their precise sexual systems. All floral characters of this taxon were examined by using a stereo microscopy. The nutlet size and production were compared between two distinct morphs (i.e., hermaphrodites and females), and pollen viability test of hermaphrodite and intermediate phenotype (i.e., individuals with a mixture of females and perfect flowers) was also observed by light microscopy (LM). All of the investigated floral characters of G. longituba are significantly different from one sexual morph to another. Hermaphroditic plants were larger than the female ones in corolla width and length, calyx length, filament length, anther length, and style length (all P < 0.0001, respectively). However, the nutlet width of the female plants was larger than those of the hermaphrodites (P = 0.013). Nutlet production of females was higher than hermaphrodites in Na-Ju population [H (Hermaphrodite): ca. 17.76%, F (Female): ca. 37.45%], but in Mun-San population was no significant difference between these sexual morphs (H: ca. 57.52%, F: ca. 53.16%). We have found significant differences between the fertile pollen grain of hermaphrodite and sterile pollen grain of intermediate phenotype based on pollen size and viability. The results of the present study suggest that compensation (flower size dimorphism, seed set, and pollen viability) is one of the main mechanisms in order to maintain female plants in gynodioecious G. longituba.

• The Plant Pathology Journal
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• 제34권5호
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• pp.393-402
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• 2018

Rice world production is affected due to the growing impact of diseases such as bacterial panicle blight, produced by Burkholderia glumae. The pathogen-induced symptoms include seedling rot, grain rot and leafsheath browning in rice plants. It is currently recognized the entrance of this pathogen to the plant, from infected seeds and from environmental sources of the microorganism. However, it is still not fully elucidated the dynamics and permanence of the pathogen in the plant, from its entry until the development of disease symptoms in seedlings or panicles. In this work it was evaluated the infection of B. glumae rice plants, starting from inoculated seeds and substrates, and its subsequent monitoring after infection. Various organs of the plant during the vegetative stage and until the beginning of the reproductive stage, were evaluated. In both inoculation models, the bacteria was maintained in the plant as an endophyte between $1{\times}10^1$ and $1{\times}10^5cfu$ of B. $glumae.g^{-1}$ of plant throughout the vegetative stage. An increase of bacterial population towards initiation of the panicle was observed, and in the maturity of the grain, an endophyte population was identified in the flag leaf at $1{\times}10^6cfu$ of B. $glumae.g^{-1}$ fresh weight of rice plant, conducting towards the symptoms of bacterial panicle blight. The results found, suggest that B. glumae in rice plants developed from infected seeds or from the substrate, can colonize seedlings, establishing and maintaining a bacterial population over time, using rice plants as habitat to survive endophyticly until formation of bacterial panicle blight symptoms.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.25-25
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• 2017

Inflorescence architecture mainly contributes to final grain yield in crops. Sorghum inflorescence is basically composed of one fertile sessile spikelet (SS) and two infertile pedicellate spikelets (PS). To identify regulatory factors involved in the inflorescence architecture, we screened an EMS mutagenesis population from the pedigreed sorghum mutant library. We found inflorescent architecture mutants, named as multi-seed mutants, msd, with gained fertile ability in PS and also an increased number of floral branches. In natural sorghum populations, it is not common that are fertile. A detailed dissection of developmental stages of wild type and msd1 mutant described that the PS in wild type do not have floral organs, including ovary, stigma, filament and anther, while the msd1 mutants generate intact floral organ in the sessile spikelet. We found MSD1 encoded a TCP transcription factor using bulk segregant analysis (BSA) of F2 population, and was a strongly enriched expression during inflorescence developmental stages. We proposed that MSD1 functions to suppress floral organ maintenance at PS during inflorescence development in Sorghum. To explore the regulatory network associated with PS fertility, whole genome expression profiling was performed at 4 different developmental stages in 6 various tissue types between wild type and msd1. Taken together, we demonstrated that MSD1 was involved in the plant hormone and maybe influenced program cell death in PS via the activation of plant hormonal pathway.

• 한국작물학회지
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• 제41권3호
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• pp.354-361
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• 1996

신속하고 정확한 근적외선 분광분석법으로 품질분석의 효율성을 증대하기 위하여 화학성분의 변이분포가 검량식 작성과정에 미치는 영향과 측정 정확성에 미치는 관계를 구명하여, 근적외선 분광광도계의 이용 효율성 제고를 위한 기초자료를 얻고자 실시한 실험의 결과는 다음과 같다. 1. 보리 전분에 대한추정치 표준오차는 변이폭이 증대될수록 증가하는 경향을 보였으며, 상관계수도 변이폭이 증대될수록 0.872에서 0.883으로 다소 높아지는 경향을 나타내었다. 2. $eta$-glucan과 단백질은 변이폭이 증대될수록 추정치 표준오차는 낮아지고 상관계수는 높아지는 결과를 보여, 근적외선 분광분석법의 이용성 향상을 위하여서는 이들 성분의 함량변이 확대가 필요할 것으로 생각되었다. 3. 회분은 첫번째와 두번째 group에서는 유의성이 인정되지 않았으나, 세번째 group에서는 상관계수가 0.743으로 유의성이 인정되어 회분함량의 경우에는 어느 정도의 변이폭이 있어야만 근적외선 분광분석법이 가능할 것으로 생각되었다. 4. 겉보리 성분 중 전분과 회분은 재검토가 이루어져야 할 것으로 생각되었으며, $\beta$-glucan과 단백질은 근적외선 분광분석법의 적용이 가능하여 분석의 효율성이 증대될 것으로 생각되었다.

• 한국농공학회지
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• 제33권3호
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• pp.51-62
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• 1991

A comprehensive laboratory investigation of the liquefaction characteristics of Jumunjin standard sand. Seoul sand and Hongsung sand was peformed by the undrained cyclic triaxial compression test under different relative densities, confining pressures and cyclic deviator stresses. The results obtained are as follows ; 1. Liquefaction potential was dominated by the stress ratio at a given number of cycle. That is, the number of cycle required to cause initial liquefaction became samller as the stress ratio increased. 2. Liquefaction potential of a sand was infliuenced by initial relative density or void ratio. Under a given relative density. liquefaction potential of Jumunjin standard sand and Seoul sand was smaller than that of Hongsung sand. 3. The pore pressure ratio of Hongsung sand was the smallest three under a given relative density and stress ratio, and it showed higher value when the cyclic stress and the shear strain were high. 4. An excessive pore pressure ratio not found when initial shear was smaller than 0.01%, and the pore pressure ratio started to increase when initial shear became greater than 0.01%. 5. Soil texture is an important factor to cause liquefaction, and liquefaction potential decreased a the mean grain size decreased. however the sand having fine grain such as Hongsung sand showed somewhat higher liquefaction potential. 6. Based on the analysis of the specimens whose number of the cycles to cause liquefaction was 8~12, it was found that the relationship between density and stress ratio was linear. The curves for Hongsung sand was steeper than the other. 7. From the above results and the method suggested by Seed-Idriss, it may be considered that the damages by Hongsung earthquake was not directly caused by liquefaction.

• 한국작물학회지
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• 제53권2호
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• pp.187-195
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• 2008

Polyphenol oxidase (PPO) is implicated in discoloration of white salted noodles and other wheat based foods. PPO activity was evaluated to determine the effect on discoloration of noodle dough sheets prepared from 25 Korean wheat flours during storage and to screen experimental lines with low PPO activity in 52 Korean wheats. PPO activity was assayed with whole-seed and performed with L-dihydroxyphenylalanine (L-DOPA) as substrates. Absorbance by L-DOPA assay of 25 Korean wheats was from 0.285 to 1.368 at 475 nm. PPO activity was significantly related with grain characteristics, including 1000-kernel weight and grain colors. In flour characteristics, PPO activity positively correlated with ash and protein content (r = 0.658, P < 0.001 and r = 0.424, P < 0.05, respectively) and negatively correlated with $L^*$ value of flour (r = 0.412, P < 0.05). In the changes of color of noodle dough sheet, $L^*$ and $b^*$ values consistently decreased and $a^*$ value increased during storage. PPO activity negatively correlated with $L^*$ value of noodle dough sheet during storage (r = 0.566, P < 0.01 at 2 hr, r = 0.547, P < 0.01 at 24 hr, and r = 0.509, P < 0.01 at 48 hr). But, no significant relationship was found in between PPO activity, $a^*$ and $b^*$ values during storage. The 52 Korean wheat lines examined in this study were divided into 3 different groups, low (< 0.500), medium (0.501-0.999) and high level (> 1.000), on the basis of the level of PPO activity. Twenty two Korean wheat lines showed low level of PPO activity and Suwon 252, 277 and 280 showed lower PPO activity (< 0.200) than others.

• 한국작물학회지
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• 제21권1호
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• pp.87-91
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• 1976

개간지에서 대두를 재배함에 있어서 시비의 효과를 구명하기 위하여 개간지에는 10a당 N.P.K:4.10.8 kg의 시용구를 비롯하여 무비구를 포함한 6개 처리구를 설치하고 효과를 비교하고저 따로 숙전에다 N.P.K:4.10.8 kg의 시비구를 설치하여 수량과 성분함량을 조사한 결과를 요약하면 다음과 같다. 1. 개간지는 같은 수준의 시비에서도 숙전보다 청예수량이나 자실수량이 극히 적었고 자실의 단백질함량도 적었다. 2. 같은 개간지내에 있어서는 질소의 시용량이 많을수록 자실수량이 많았다. 3. 자실성분에 있어서 숙전은 단백질과 지방함량이 개간지보다 많았고 탄수화물은 개간지가 숙전보다 많은 경향이었다. 4. 개간지에 있어서 자실성분함량은 처리간에 유의성이 인정되지 않았다. 5. 수량과 밀접한 관계가 있는 100입중, 1주협수 간장 간중등은 자실수량과 정의 상관을 나타냈으며 1%수준의 유의성이 인정되었다.